Today I hunted down a bug in Visual Studio 2005 that annoyed me tremendously for the past couple of weeks. Starting from this certain point in time, without any reason whatsoever (maybe a sun burst targeting my office desk or something), Visual Studio started littering my source tree with folders named Visual Studio 2005. In these directories there was another directory named Backup Files.
At first I thought that the configuration options for Visual Studio were wrong. I checked the directory settings for Environment/Import and Export Settings and Project and Solutions. Everything seemed in order.
After some journey through the Windows registry, I found this inconsistent value for the HKEY_CURRENT_USER\Software\Microsoft\Visual Studio\8.0\VisualStudioLocation key. It was set to the value "VisualStudioProject" to be more precise. Changing this value to the correct path in the Document and Settings directory solved he problem.
This is a very specific problem that really affected my mood. It even put these backup folders in places that didn't had any source file. Someone at Microsoft should get fired for this ;-) (no, just kidding). An IDE from JetBrains that targets .NET with Boo and IronRuby as first class citizens. That would be cool, don't you think?